The present invention relates to log-feed apparatus used in a log-feed assembly, and in particular, to an apparatus having a spiked feed roll and a gear reducer through which drive is imparted to the feed roll--with the latter substantially shock-isolated from the former.
In the usual log-debarking system, a log is fed along a transport axis through a debarking ring by a pair of log-feed assemblies mounted on either side of the ring. Typically, each log-feed assembly includes three log-feed apparatus having elongated arms which are mounted for cooperative swinging of their free ends toward and away from the transport axis. A spiked feed roll is carried on the swinging end of each arm for engaging an outer surface portion of a log. The feed rolls are rotatably driven, at identical speeds, to advance a log along such axis.
In one type of roller feed apparatus known in the prior art, a feed roll therein is mounted directly on the output shaft of a gear reducer carried adjacent the outer, swinging end of the arm. The gear reducer, in turn, is powered by a hydraulic motor which is mounted on the arm and coupled to the gear reducer by rigid mechanical coupling. Alternatively, the driving motor may be located on the assembly frame, being rigidly coupled to the associated feed roll by a complex right-angle gear reducer.
A characteristic operational feature of a log-debarking system of the general type described is that the feed rolls experience considerable radially directed shock as the roller arms track with the surface of a log. In the prior art log-feed apparatus just-described, such radial shock is transmitted directly to the associated gear reducer and other driving components, with the result that all such components experience significant abuse, and may require frequent repair or replacement. Such drive components are stressed further by torsional shock which occurs as the associated power-driven feed roll encounters irregularities on a log's surface.
Aggravating the effect of radial and torsional shock in many log feeders of the type mentioned in prior art is the presence of rigid drive coupling throughout.
It is one object of the present invention to provide, in a log-feed assembly, log feed apparatus which substantially reduces radial and torsional shock transmitted from a feed roll in the apparatus.
A more specific object of the invention is to provide, in such an apparatus, a feed roll journal construction which isolates components in the roll's drive train from substantially all but torsional loads transmitted by the roll.
Still another object of the present invention is to provide, in such an apparatus, a yieldable drive coupling between a gear reducer and a drive motor in the drive train for the apparatus.
It is yet another object of the invention to provide such an apparatus which is simple in construction.
The log-feed apparatus of the present invention is constructed for use in a log-feed assembly used in advancing a log along a transport axis in a log-debarking system. The apparatus includes an elongated arm mounted at an inner arm end for swinging of its outer end toward and away from the transport axis. A spiked feed roll mounted on the outer arm end for rotation about the arm's long axis is carried on a shaft which is journaled on the arm by a pair of axially spaced bearings. A motor mounted adjacent the inner arm end acts through a gear reducer mounted on the arm, intermediate the arm ends, to drive the feed roll. The motor is drivingly connected to the input of the gear reducer by a flexible belt drive, with the output of the gear reducer being drivingly connected to the shaft carrying the feed roll by a rotary shaft coupling. The shaft and bearings journaling the roll on the arm act to isolate all other drive components for the roll from substantially all but torsional loads transmitted by the feed roll. The isolated shock loads are transmitted directly through the bearings to the arm.
These and other objects and features of the present invention will become more fully apparent when the following detailed description of a preferred embodiment of the invention is read in conjunction with the accompanying drawings, wherein: